Ethers are particularly useful as solvents. Since the boiling points of ethers differ according to the composition, it is desirable to have available ethers of varying compositions in order to meet a variety of boiling point requirements for solvents.
Industrially, symmetrical ethers have been produced by sulfuric acid dehydration of alcohols. Another manner of preparing symmetrical ethers has been by the Williamson synthesis which uses an alkyl halide and a sodium alkoxide (both alkyl groups being the same).
The commonly-assigned application, referred to above, concerns a process for preparing ethers by the reaction of an organic compound, containing a halogen or alkyl sulfate group, with an alkali metal hydroxide, in aqueous solution, in the presence of a catalytic amount of a quaternary salt. I have found that use of certain betaines gives improved results, particularly when higher temperatures are used.